I started to experience an error today with the quantmod package. Anybody else have the same error when running this code (or requesting symbols in general)?
library(quantmod)
getSymbols("CPIAUCNS",src="FRED")
Error:Error in download.file(paste(FRED.URL, "/", Symbols[[i]], "/", "downloaddata/", :
cannot open URL 'http://research.stlouisfed.org/fred2/series/CPIAUCNS/downloaddata/CPIAUCNS.csv'
The URL itself works fine.
FRED changed the URL scheme from http:// to https://. I'm working on determining a patch that will work on all platforms. The current code still works for me on Windows if --internet2 is set.
On unix-alikes, one potential solution is to add method="curl" or method="wget" to the download.file call in getSymbols.FRED.
Another (temporary) solution is to call one of the following before the actual getSymbols script:
options(download.file.method="libcurl")
oroptions(download.file.method="wget")
oroptions(download.file.method="wininet")
The first option works for me (on Mac).
Thanks Paul Gilbert from Rmetrics (bottom post)
The problem appeared yesterday:Cannot verify certificate for stlouisfed.org issued by GoDaddy.
A workaround:
temp = tempfile()
download.file(url="http://research.stlouisfed.org/fred2/series/DAAA/downloaddata/CPIAUCNS.csv",destfile=temp, method="libcurl")
result <- read.csv(temp,na.string=".")
I hope having to use this fix is temporary.
Here is solution that works for me, assuming you trust FRED's SSL certificate.
All you need to do is adding the following extra line of code before executing getSymbols:
options(download.file.method = "wget", download.file.extra = c("--no-check-certificate"))
Example:
getSymbols("M2", from = start_date, to = end_date, src = "FRED")
[1] "M2"
str(M2)
An ‘xts’ object on 1980-11-03/2015-10-05 containing:
Data: num [1:1823, 1] 1591 1593 1596 1597 1596 ...
- attr(*, "dimnames")=List of 2
..$ : NULL
..$ : chr "M2"
Indexed by objects of class: [Date] TZ: UTC
xts Attributes:
List of 2
$ src : chr "FRED"
$ updated: POSIXct[1:1], format: "2015-10-21 11:01:39"
来源:https://stackoverflow.com/questions/31188023/quantmod-error-cannot-open-url